Engine starter bolts size

Hello guys,

Can anyone please share which spanner size are the correct factory starter bolts ?

Also a starter at the bench turning the pinion gear anticlockwise (with hand, no power) makes a clicking noise , is this normal or something is bad/defective ?

Thank you !!!

The spanner is 3/4 inch (which should be a 1/2 inch diameter bolt):
https://i.imgur.com/r1ba96Ll.jpg

https://i.imgur.com/iW6C8Mrl.jpg

Sorry - not sure about the clicking noise.

Thank you so much for the info !!!